Air brake systems such as are used on large trucks and trailers, for example, include one or more air brake chambers. Each air brake chamber may be generally referred to as a brake can which is fastened at its open end to a brake can tube on the vehicle. A strong wedge spring is compressed within the brake can when the brake can and brake can tube are fastened together.
When service or repair work is performed on the air brake system it is necessary to remove the brake can from the brake can tube. Because the compressed wedge spring can exert tremendous outward force, it is necessary to exercise extreme caution when loosening and removing the brake can; otherwise the brake can may be forced away from the brake can tube with such great energy that a workman may become injured if struck by a flying brake can. Also, if there is air pressure in the air line when loosening the brake can, the workman could become injured because the, air pressure could force a violent separation of the brake can from the brake can tube.
Problems of a similar nature are encountered after repairs have been made and it is necessary to install the brake can onto the brake can tube again. Typically the brake can and brake can tube each include a flange around the periphery of their open end, and these flanges are forced together and then captured in a retention ring. The retention ring has two ends which are secured together by means of a bolt and nut after the retention ring is placed around the abutting flanges of the brake can and brake can tube. If the retention ring is not properly in place, or is not properly tightened, the compressed wedge spring may force the brake can and brake can tube apart with great force, in the manner explained above.
Various types of clamping tools have been previously described. See, for example, U.S. Pat. Nos. 1,953,926; 2,899,995; 3,144,793, 3,314,319; 3,395,724; 3,498,157;, 3,585,704; 4,235,073; 4,344,215; 4,542,583; and 4,601,221. See also French Patent No. 1,297,140. None of such prior tools, however, are suitable for use in accordance with the requirements of this invention.